U.S. patent application number 16/760771 was filed with the patent office on 2020-08-13 for spray device.
The applicant listed for this patent is Robert Bosch GmbH. Invention is credited to Dieter Amesoeder, Hans-Arndt Freudigmann, Jochen Glasbrenner, Olaf Ohlhafer, Helmut Schomburg.
Application Number | 20200253185 16/760771 |
Document ID | 20200253185 / US20200253185 |
Family ID | 1000004829311 |
Filed Date | 2020-08-13 |
Patent Application | download [pdf] |
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United States Patent
Application |
20200253185 |
Kind Code |
A1 |
Glasbrenner; Jochen ; et
al. |
August 13, 2020 |
SPRAY DEVICE
Abstract
A spray device for deploying liquids, in particular for
agricultural purposes. The spray device includes at least one spray
nozzle for spraying the liquid and includes at least one mixing
unit, which encompasses at least one mixing chamber. The mixing
chamber includes at least one first inlet for a carrier liquid, at
least one second inlet for an active agent liquid, and at least one
outlet. The mixing unit encompasses at least one control member for
setting a mixing ratio of carrier liquid and active agent liquid.
The control member is rotatably mounted in the mixing chamber, a
through-flow cross-section of at least the first inlet and/or the
second inlet being set depending on the rotation position of the
control member.
Inventors: |
Glasbrenner; Jochen;
(Stuttgart, DE) ; Schomburg; Helmut; (Deufringen,
DE) ; Ohlhafer; Olaf; (Erligheim, DE) ;
Amesoeder; Dieter; (Ludwigsburg, DE) ; Freudigmann;
Hans-Arndt; (Tuebingen, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Robert Bosch GmbH |
Stuttgart |
|
DE |
|
|
Family ID: |
1000004829311 |
Appl. No.: |
16/760771 |
Filed: |
October 26, 2018 |
PCT Filed: |
October 26, 2018 |
PCT NO: |
PCT/EP2018/079372 |
371 Date: |
April 30, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A01M 7/0092 20130101;
B05B 12/1418 20130101; B05B 7/32 20130101; B05B 13/005 20130101;
A01M 7/0042 20130101 |
International
Class: |
A01M 7/00 20060101
A01M007/00; B05B 7/32 20060101 B05B007/32; B05B 12/14 20060101
B05B012/14; B05B 13/00 20060101 B05B013/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 10, 2017 |
DE |
10 2017 220 030.8 |
Claims
1-14. (canceled)
15. A spray device for deploying liquids for agricultural purposes,
the spray device comprising: at least one spray nozzle for spraying
the liquid; and at least one mixing unit including at least one
mixing chamber, the mixing chamber including at least one first
inlet for a carrier liquid, at least one second inlet for an active
agent liquid, and at least one outlet, the mixing unit further
including at least one control member for setting a mixing ratio of
carrier liquid and active agent liquid, wherein the control member
is rotatably mounted in the mixing chamber, a through-flow
cross-section of at least the first inlet and/or the second inlet
being set depending on a rotation position of the control
member.
16. The spray device as recited in claim 15, wherein the control
member is a camshaft and at least one of the first and second
inlets includes a valve actuatable via the camshaft.
17. The spray device as recited in claim 15, wherein the valve
includes a valve element which is movably mounted and
spring-preloaded in a direction of the camshaft and rests tightly
against a valve seat of the valve, wherein the valve element closes
the at least one of the first and second inlets, in a state in
which it is not actuated by the camshaft.
18. The spray device as recited in claim 15, wherein the control
member is a camshaft, and wherein a valve, actuatable by the
camshaft, is assigned to several inlets of the mixing chamber or to
each of the inlets of the mixing chamber.
19. The spray device as recited in claim 15, wherein the at least
one control member includes two control members rotatably mounted
in the mixing chamber, an activatable servomotor being assigned to
each of the control members to rotate the control members.
20. The spray device as recited in claim 19, wherein each of the
two control members is a camshaft, wherein the mixing chamber
includes several inlets each having a respective valve, at least
two of the valves in each case, being assigned to each of the
camshafts.
21. The spray device as recited in claim 20, wherein each of the
camshafts includes at least one respective cam in each case for
each assigned valve.
22. The spray device as recited in claim 20 wherein each of the
camshafts includes one shared cam for the at least two assigned
valves.
23. The spray device as recited in claim 15, wherein the control
member is a rotary valve which includes at least one through-flow
opening for at least one of the first and second inlets, the rotary
valve configured to be brought into an overlap rotation position
with the at least one of the first and second inlets.
24. The spray device as recited claim 15, wherein the at least one
first inlet includes at least two first inlets for the carrier
liquid.
25. The spray device as recited in claim 15, wherein the mixing
unit is located upstream from a spray nozzle of the at least one
spray nozzle, or multiple spray nozzles of the at least one spray
nozzle, and wherein the spray nozzle is in a field sprayer.
26. The spray device as recited in claim 15, wherein a detent
device and/or a self-locking gear unit is assigned to the control
member.
27. The spray device as recited in claim 15, wherein the spray
device includes one or multiple active agent liquid tanks, and one
carrier liquid tank, which are connected to the mixing unit.
28. The spray device as recited in claim 26, wherein a pump device
is assigned to the active agent liquid tank and to the carrier
liquid tank for delivering liquid to the mixing unit.
Description
FIELD
[0001] The present invention relates to a spray device for
deploying liquids, in particular for agricultural purposes,
including at least one spray nozzle for spraying the liquid and
including at least one mixing unit, which encompasses at least one
mixing chamber, the mixing chamber including at least one first
inlet for a carrier liquid, at least one second inlet for an active
agent liquid, and at least one outlet, and the mixing unit
encompassing at least one control member for setting a mixing ratio
of carrier liquid and active agent liquid.
BACKGROUND INFORMATION
[0002] In the case of present-day agricultural plant protection
measures, the spray mixture made up of at least one active agent,
in particular an active agent liquid, such as a plant protection
agent, as well as a carrier liquid, in particular water, must be
premixed before the actual application onto a field. At the end of
the application, the tank providing the particular agent generally
must be completely emptied on the field and cleaned. It is
therefore barely possible to respond to the condition of the field
and to the actual local need for plant protection agent. The
complete mixed spray mixture is therefore completely deployed on
the field.
[0003] In some conventional systems, the active agent liquids are
carried along, undiluted, in a separate tank and are mixed with the
carrier liquid only as needed during the deployment onto the field.
For this mixing process, it is necessary to be able to meter the
active agent liquid together with the carrier liquid according to
demand. This metering process is also referred to as direct feeding
and requires a complex configuration of a spray device, which must
provide valves, and the like, necessary therefor.
[0004] Spray devices of the type mentioned above are available in
the related art. German Patent Application No. DE 10 2006 059 193
A1, for example, describes a spray device, which encompasses a
mixing chamber, to which a carrier liquid as well as an active
agent liquid, in particular a plant protection agent, are
suppliable. In this case, it is provided to initially feed the
active agent liquid into at least one bypass line for predilution,
the bypass line containing the active agent prediluted with the
carrier liquid emptying into a carrier liquid line leading to
multiple spray nozzles. In order to affect the mixing or the ratio
of carrier liquid and active agent liquid, multiple outlet valves
or adjusting valves, activatable independently of one another and
each including one valve element, as a control member, are present,
which are located upstream from the liquid lines forming the mixing
chamber.
[0005] One further conventional spray device, for example, is
describe in German Patent Application No. DE 31 40 441 A1. This
spray device includes a metering pump, which is designed as a
piston pump, carrier liquid and active agent liquid being combined
in the metering pump, so that the metering pump itself operates as
a mixing unit including a mixing chamber and the pistons operate as
control members.
[0006] Moreover, German Patent Application No. DE 39 08 963 A1
describes a spray device, including metering pumps, which pump the
active agent liquid as well as the carrier liquid into a mixing
chamber as necessary in a desired mixing ratio.
SUMMARY
[0007] An example spray device in accordance with the present
invention may have the advantage that a particularly compact mixing
unit of the spray device is made available, which has a simple
operation and a low likelihood of failure. In addition, due to its
compact design, an installation space-saving embodiment is ensured,
which also saves weight, so that it is easily possible to carry the
mixing unit along with the spray device. For this purpose, the
spray device according to the present invention provides that the
control member is rotatably mounted in the mixing chamber, a
through-flow cross-section of the first inlet and/or the second
inlet being set depending on the rotation position of the, in
particular, only one control member. Therefore, the mixing ratio is
affected by a control member situated in the mixing chamber,
whereby a particularly compact embodiment is achieved. Due to the
rotary mounting of the control member, a simple adjustment of the
desired through-flow cross-section of the first inlet and/or of the
second inlet is settable. Optionally, a through-flow cross-section
of the outlet is also settable via the rotation position. In
addition, more than only two inlets may also be present and may be
operated as described above with the aid of the control member.
[0008] In particular, in accordance with the present invention, it
is provided that the control member is designed as a camshaft and
that at least one of the inlets encompasses a valve actuatable with
the aid of the camshaft. As a result, a particularly simple
mechanical actuation of a valve assigned to the particular inlet is
made possible. Conventional cam technologies may be accessed in
this case, so that a low design complexity is necessary. In
addition, a particularly robust and permanently functioning
approach is provided via the mechanical actuation. In addition, due
to the profile of the outer circumference of the camshaft, a
chronological sequence of the opening behavior of the particular
valve is settable, in order to ensure an optimal mixing.
[0009] According to one preferred refinement of the present
invention, it is provided that the particular valve encompasses a
valve element, which is movably mounted and spring-preloaded in the
direction of the camshaft and rests tightly against a valve seat of
the valve, closing the affected inlet, in a state in which it is
not actuated by the camshaft. The particular valve therefore
encompasses a movable valve element, which, in the normal state, or
a state in which it is not actuated by the camshaft, rests against
a valve seat in a sealing manner and, as a result, closes the
affected or assigned inlet/access. By turning the camshaft, the
valve element is displaced by the camshaft counter to the spring
force, so that it assumes a distance to the valve seat, whereby the
through-flow cross-section is released and active agent liquid or
carrier liquid may flow through the access opened in this way. Due
to the spring preload, it is ensured that the valve element always
reliably returns to the valve seat and a forcible control for the
valve element is present at the camshaft.
[0010] Moreover, it is preferably provided that a valve actuatable
by the camshaft is assigned to multiple inlets in each case, in
particular to each inlet of the spray device. The valve is designed
as described above. As a result, with the aid of one and the same
camshaft, multiple valves of the spray device or of the mixing unit
are simultaneously actuatable, one valve being opened and another
valve being closed depending on the rotation angle position of the
camshaft. As a result, a simple and reliable actuation of all
valves of the mixing unit is provided.
[0011] Moreover, it is preferably provided that the mixing unit
encompasses two control members rotatably mounted in the mixing
chamber, a separate, activatable control actuator, in particular,
an electric motor, being assigned to each of the control members,
in order to turn the particular control member. Due to the
provision of at least two control members, sections of the mixing
chamber--as viewed in the axial extension of the particular control
member or in the longitudinal extension of the particular
rotational axis--or existing valves and/or inlets and/or the outlet
are actuatable independently of one another, so that an enhanced
availability of the spray device is achieved.
[0012] It is particularly preferred when each of the two control
members is designed as a camshaft, at least one of the valves, in
particular, at least two of the valves in each case, being assigned
to each camshaft. In addition, one valve may be assigned to one of
the camshafts and two or more valves may be assigned to the other
camshaft. This yields a variable mixing of different active agent
liquids as well, which may be fed to a carrier liquid according to
demand.
[0013] Preferably, the particular camshaft encompasses one cam in
each case for the particular assigned valve. Due to the shape of
the cam, the particular valve is actuated according to the rotation
position of the camshaft.
[0014] Alternatively, the camshaft includes a shared cam for at
least two assigned valves, the valves being situated next to one
another or one behind the other as viewed in the direction of
rotation of the cams. In an arrangement one behind the other, the
valves are actuated one after the other, whereby the valves are
settable having different through-flow cross-sections. If the
valves are situated next to one another, however, as viewed in the
circumferential direction, they are simultaneously actuated by the
same cam, whereby they each release the same through-flow
cross-section.
[0015] Moreover, it is preferably provided that the control member
is a rotary valve, which includes at least one through-flow opening
for at least one of the inlets, which may be brought into an
overlap position with the inlet. Depending on the size of the
overlap of the inlet and the through-flow opening, a through-flow
cross-section is released. Due to the simpler design as a rotary
valve, the mixing unit is configured to be more compact as compared
to the approach including a camshaft. Due to the provision of
multiple through-flow openings, each of which is assigned to at
least one of the inlets and/or the outlet, in addition, a flexible
configuration of the combination of the active agent liquid or
active agent liquids with the carrier liquid is ensured.
[0016] According to one preferred refinement of the present
invention, it is provided that at least two first inlets for the
carrier liquid are present. As a result, it is possible to mix, in
a simple way, a different quantity of carrier liquid with a certain
active agent liquid, in particular with multiple existing active
agent liquids, in order to set an optimal spray mixture, which is
supplied through the outlet to the particular spray nozzle.
Alternatively, in particular, only one first inlet is present.
Moreover, it is preferably provided that the mixing unit is located
upstream from a spray nozzle, in particular a field sprayer, or
multiple spray nozzles or field sprayers. If the mixing unit is
located upstream from a spray nozzle, and if the spray device
preferably encompasses multiple spray nozzles, a separate mixing
unit is located upstream from each spray nozzle, whereby an
individual admixing of carrier liquid and active agent liquid takes
place at the spray nozzle itself, whereby, on the one hand, an
advantageous mixing is achieved and, on the other hand, the volume,
which must be rinsed out during a cleaning, is minimized and, in
addition, the function of a single nozzle shut-off may be
implemented by the mixing unit itself. If the mixing unit is
located upstream from multiple spray nozzles, in particular a
so-called partial width of spray nozzles, these are all acted upon
with the desired ratio of active agent liquid or active agent
liquids and carrier liquid by one and the same mixing unit.
[0017] According to one preferred refinement of the present
invention, it is provided that a servomotor, in particular a
position-controlled servomotor, preferably an electric motor, is
assigned to each control member of the mixing unit for the
displacement thereof. With the aid of the servomotor, a simple and
prompt displacement of the control member and, therefore, a prompt
setting of the particular desired through-flow cross-section or
mixing ratio is settable. Preferably, the servomotor and/or the
control member coupled thereto include(s) a detent unit or a
self-locking unit. This ensures that, for the case in which the
electric motor or the servomotor is not activated, the particular
control member remains in the desired rotation position, in order
to maintain the set through-flow cross-section or the set
through-flow cross-sections and the desired mixing ratio. The
detent unit may be implemented, for example, with the aid of ball
detent seats and the self-locking may be achieved with the aid of a
severely reduced gear unit between the servomotor and the control
member. As a result, a current consumption is minimized, overall,
during operation.
[0018] Moreover, the spray device preferably encompasses one or
multiple active agent liquid tanks, as well as at least one carrier
liquid tank. Preferably, pump units are assigned to each of the
active agent liquid tanks and to the carrier liquid tank, which
deliver the particular liquid in the direction of the mixing unit
as necessary.
[0019] The present invention is to be explained in greater detail
below with reference to the figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows an advantageous spray device for deploying
liquids for agricultural purposes in accordance with an example
embodiment of the present invention.
[0021] FIG. 2 shows an advantageous mixing unit of the spray device
in accordance with the present invention in a simplified detailed
view.
[0022] FIG. 3 shows an advantageous refinement of the mixing unit
in a simplified representation.
[0023] FIG. 4 shows one further exemplary embodiment of the spray
device.
[0024] FIG. 5 shows an alternative exemplary embodiment of the
spray device.
[0025] FIG. 6 shows one further exemplary embodiment of the
advantageous mixing unit.
DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS
[0026] FIG. 1 shows, in a simplified representation, an example
spray device 1, which encompasses a vehicle 2 designed as a
tractor, which carries a spray system 3, including a plurality of
spray nozzles 4, the spray nozzles 4 being distributed, next to one
another, over a crossbar 5. Vehicle 2 pulls crossbar 5 and spray
nozzles 4 behind itself, so that spray nozzles 4 are situated above
a ground 6, in order to apply plant protection agent onto the
ground and plants possibly located thereon.
[0027] For this purpose, vehicle 2 carries multiple tanks 7, 8, 9
and 10, a liquid active agent A, B, and C, in particular prediluted
with a carrier liquid, being kept available in tanks 7, 8 and 9,
respectively, and a carrier liquid TF, in particular water, being
kept available in tank 10. The predilution is alternatively carried
out/implemented with the aid of a premixing unit located upstream
from the mixing unit. Tanks 7 through 10 are connected to spray
nozzles 4 with the aid of one or multiple mixing units, which are
to be discussed in greater detail in the following. In order to
deliver the particular liquid, a pump unit 11, 12, 13 and 14 is
assigned to each tank, with the aid of which the particular liquid
is removable and suppliable to the mixing unit described below.
While three different active agent product tanks 7, 8 and 9 are
shown and described in the following exemplary embodiment, it goes
without saying that spray device 1 may also encompass more or fewer
active agent tanks 7, 8, 9.
[0028] FIG. 2 shows, in a simplified sectional representation,
aforementioned advantageous example mixing unit 15. Mixing unit 15
includes a housing 16, in which two control members 17, 18 are
rotatably mounted. For this purpose, housing 16 provides a mixing
chamber 19, in which control members 17, 18 are situated. Mixing
chamber 19 is designed, in particular, in the shape of a cylinder,
so that mixing chamber 19 itself preferably forms a pivot bearing,
in particular a sliding bearing, for control members 17, 18.
Housing 16 also includes multiple inlets 20, 21, 22 and 23. Inlets
20 through 23 empty into mixing chamber 19, a valve 24, 25, 26 and
27 being assigned to each of inlets 20 through 23. Due to
particular valve 24 through 27, inlets 20 through 23 are
connectable to liquid lines connected to pump devices 11, 12, 13,
14.
[0029] Valves 24 through 27 are designed as seat valves, which each
include a valve element 28, 29, 30 and 31 mountable radially with
respect to the rotational axis of mixing chamber 19. Valve elements
28 through 31 are each actuatable with the aid of control members
17, 18 counter to the force of a preload spring 32, 33, 34, 35.
Particular preload spring 32 through 35 pushes valve element 28
through 31, in the direction of control member 17 or 18 into a
valve seat of valve 24 through 27, in order to sealingly close
inlet 20 through 23.
[0030] Control members 17, 18 are designed, in this case, as
camshafts, which each include a cam 36 or 37, with the aid of which
two of the valves 24, 26 or 25, 27, positioned radially opposite
one another, are actuatable. For this purpose, cams 36 and 37 each
interact with a valve stem of particular valve element 28 through
31. Due to the cams, the particular valve elements 28 through 31
may be pushed out of the particular valve seat counter to the force
of the preload spring, so that a through-flow cross-section is
released in each case, which makes it possible for liquid delivered
to particular inlet 20 through 23 to penetrate mixing chamber
19.
[0031] Depending on the rotation position of particular control
member 17, 18, a through-flow cross-section is therefore released,
which permits the penetration of the particular liquid into mixing
chamber 19, liquids being mixed with one another within mixing
chamber 19. Through an outlet 38 formed in housing 16, the
commingled mixture or the spray mixture produced in this way flows
out of mixing unit 15 and to one or several of the aforementioned
spray nozzle(s) 4.
[0032] In order to displace particular control member 17, 18 or the
camshaft, it is provided that a separate servomotor 39 or 40 is
assigned to each control member 17, 18. Servomotors 39, 40 are
preferably designed as electric motors, which are coupled to
control member 17, 18, or to the particular camshaft directly or
with the aid of an, in particular, self-locking gear unit.
Optionally, a detent unit, such as a ball detent unit, may be
assigned to each of the control members 17, 18 and/or servomotors
39, 40, which prevents an undesirable displacement of control
member 17, 18.
[0033] FIG. 3 shows mixing unit 15 according to a first exemplary
embodiment in a schematic representation. Optionally, two of the
inlets 23 or valves 27 are provided, through which the carrier
liquid is suppliable to mixing chamber 19. In addition, the lines
for various liquids A, B, C and TF are shown, simplified, in FIG.
3. With the aid of the displacement of the camshafts, the different
through-flow cross-sections are settable, in order to achieve a
desired mixing ratio. Preferably, the active agent liquids have
already been premixed with carrier liquid in tanks A, B, C, in
order to provide for an optimal mixing ratio during operation, or
the active agent liquids are prediluted with the carrier liquid
with the aid of a premixing unit, which is located upstream from
mixing unit 15.
[0034] The profiles of cams 36, 37 of the camshaft are configured
in such a way that one or multiple valve(s) 24 through 27 is/are
opened and closed depending on the rotation angle of the particular
camshaft.
[0035] With the aid of mixing unit 15 shown in FIG. 2, in
particular, the switching positions listed in the following may be
represented:
[0036] 1.: active agent liquid A+carrier liquid water
[0037] 2.: active agent liquid B+carrier liquid water
[0038] 3.: active agent liquid C+carrier liquid water
[0039] 4.: active agent liquids A and B+carrier liquid water
[0040] 5.: active agent liquids A and C+carrier liquid water
[0041] 6.: active agent liquids B and C+carrier liquid water
[0042] 7.: active agent liquids A and B and C
[0043] 8.: mixing unit closed in its entirety
[0044] In the case of a typical application of active agent liquids
or plant protection agents, it is necessary to be able to adjust
the total application rate. For example, the total quantity of
water should remain constant during the changeover from, for
example, one of the plant protection agents to a combination of
multiple plant protection agents. Additionally, a pressure matched
to the utilized nozzle and, therefore, a volumetric flow rate,
should be set. The reason therefor is that a drop size spectrum,
which is optimal for the application of plant protection agent,
results at spray nozzle 4 only in the case of a pressure matched to
the nozzle and, therefore, a predetermined volumetric flow rate. In
one variation of the composition of the spray mixture, as shown,
for example, in the aforementioned list, it is therefore also
necessary that the total application rate for all intended
combinations is identical to the quantity matched to particular
nozzle 4. Therefore, the metered quantity of water or carrier
liquid made available in mixing unit 15 varies depending on the
selected mixing combination of active agent liquids. For example,
less water needs to be metered for switching positions 1 through 3
than for switching positions 4 through 6. For switching position 7,
no water, or less water than for switching positions 1 through 6,
needs to be metered. The control of the quantity of water depending
on the mixing combination is preferably implemented with the aid of
the variable through-flow cross-section of valve 27, through which
the carrier liquid is supplied. As one further possibility for
quantity control, it is advantageous to implement the variation of
the carrier liquid quantity with the aid of multiple individual
valves 27. This possibility is outlined in FIG. 3. The two valves
27 may be switched together or independently of one another, in
order to provide for an optimal metering of the carrier liquid.
[0045] As one further option for holding the quantity of water
nearly constant, the dilution of the plant protection agents is
preferably kept as low as possible. If, for example, the plant
protection agent is diluted, in each case, with only 5% of the
quantity of water to be deployed, then 90% of the total quantity of
water could be constantly metered, when a nozzle is open, via the
water path. Therefore, the range of the total quantity of water
deployed would be 95% (upon utilization of one plant protection
agent) up to 105% (upon utilization of three plant protection
agents A, B and C).
[0046] Advantageous mixing unit 15 may be integrated into the spray
system or spray device 1, as shown in FIG. 1, in different ways.
FIG. 4 shows a first exemplary embodiment for this purpose. It is
provided that a mixing unit 15 is located upstream from each spray
nozzle 4 or each spray nozzle 4 of a predetermined partial width I
out of a predetermined number of selected spray nozzles 4, so that
the mixing takes place directly upstream from particular spray
nozzle 4. With the aid of this system, it is possible to specify
the composition of the spray mixture separately for each spray
nozzle 4.
[0047] Alternatively, the mixing unit, as represented in FIG. 5,
may be integrated into spray device 1, it being provided, in this
case, that one mixing unit 15 is located upstream from multiple
spray nozzles 4 in each case, in particular spray nozzles 4 of a
separate partial width I, II, III or IV of existing spray nozzles
4, so that the same composition of the spray mixture may be applied
to multiple spray nozzles 4. If individual spray nozzles are to be
switched on or off, actuatable switching valves are preferably
assigned thereto.
[0048] FIG. 6 shows one further exemplary embodiment, which differs
from the exemplary embodiment from FIG. 2 in that mixing unit 15
includes a rotary valve 41, rather than one or multiple camshafts,
in mixing chamber 19. Rotary valve 41 encompasses multiple
through-flow openings 42, each of which may be brought into an
overlap position with one of the inlets 20 through 23 depending on
the rotation position of rotary valve 41, a through-flow
cross-section being released, in each case, depending on the
overlap position, and, therefore, the particular inlet being
partially or completely opened. The liquid flows are mixed within
the rotary valve 41, which is designed in the shape of a sleeve,
and are supplied to outlet 38, which is axially situated in this
case. In this case as well, a servomotor, of the type described
above, is preferably utilized as an actuator for turning rotary
valve 41. Depending on the rotation position of rotary valve 41,
certain inlets are therefore released or opened, and therefore, a
mixing ratio of plant protection agent A, B, C and carrier liquid
TF is set. In addition, instead of a rotary valve 41, two rotary
valves 41 may be situated one behind the other, to each of which a
servomotor is assigned, in order to achieve a higher variance in
the selection of the mixing ratios.
[0049] In addition to multiple radial inlets 20 through 23 and an
axial outlet 38 shown in FIG. 6, the following variants may also be
implemented: Mixing unit 15 including a rotary valve 41,
encompassing multiple axial inlets and one radial outlet,
encompassing multiple axial inlets and one axial outlet, or a
mixture thereof.
[0050] Due to the advantageous embodiment of spray device 1, a
compact and easily handleable mixture of desired active agent
liquids with a carrier liquid in a small installation space is
ensured.
* * * * *